Just a few "basic" things that come to mind when working on your trucks - some of which I learned the hard way! Sometimes welding isn't the best way! - bumpers and plow mounts are two good examples. It's tempting to just weld them on there, but if you ever want to remove it you'll be cursing! And, it's no fun trying to crawl under your truck & weld vertical & overhead. (I know, I was cursing me for welding my bumper on the last time I did body/paint on my truck) Good quality bolts (I like to use Grade 8) are the best way to attach things, I also prefer steel self-locking nuts over lockwashers or nylon insert self-locking nuts. When welding on your truck, disconnect that battery! Especially with all the computing power built into modern trucks - 'puters and welding current don't get along. Make sure your truck is parked on a level surface before you start measuring & building, and never assume that everything on the truck is square/level/symmetrical. From normal wear & tear and use, the body & suspension move around & settle into position, and every vehicle is a little different. Even brand-new ones can be slightly off - that's why fender shims were invented! Whatever it is you are making, build it to suit the truck - generally, this involves tack-welding the components together on-board, then taking the assembly off for welding - and make sure you step back & take a good look from different angles before you "commit". When doing your tacking/welding on board the truck, keep your ground clamp on your workpiece if at all possible - by this I mean if you are building a rear bumper, put the ground clamp on that bumper. The welding current has to flow in a continuous path from the machine, through the electrode, through the pieces being joined, and back out to the machine via the ground cable. Since electricity always takes the path of least resistance, if the ground clamp was at the front of the truck and you are welding at the back, that electricity might decide it's easier to run along the copper in the wiring harness. These wires are too light to carry welding current, so the result is a mess! I have seen this happen - I can honestly say it wasn't me but it WAS one of my co-workers. We smelled burning wire & wondered what was going on. Cover up that paint & glass! - when welding or grinding, remember that each spark is a tiny piece of molten metal. Think what that will do to your paint/wax! Glass is even worse, when a spark hits the glass it melts a tiny pit and there is nothing you can do once it's happened. If the window was "got" badly, it will eventually show rust stains. Replacement of the glass is the only solution once it gets burnt. So keep things covered up - even if you are grinding at the back of the truck, it's possible to spark your mirror - this is one I HAVE done. Hopefully, this can help prevent someone else from making the same mistake(s)!